Method for drawing rods and tubes of varying diameters.



L. H. BRINKMANQ METHOD FOR DRAWING RODS AND TUBES 0F VARYING DJAMETERS.

APPLICATION FILED NOV. 14. IBM. I I 130L221. Patented Apr. 22, 1919;.

4 SHEETS-SHEET I I INVENTOR ATTORNEY Mia/$4M m 4 M L. H. BRINKMAN.

METHOD FOR DRAWING RODS AND T UBES 0F VARYiNG DIAMETERS. APPLICATION FILED NOV. 14, 1911.

Patented Apr. 22,1919.

4 SHEETS-SHEET 2.

INVENTOR ATTORNEY L. H. BRINKMAN. METHOD FOR DRAWIN'G RODS AND TUB ES 0F VARYINGDIAMETERS.

APPLICATION FILED TTOV1I4. T917- Patented Apr. 22, 1919.

LEGLQQL 4 SHEETS-SHEET 3- ATTORNEY L. H J'BHINKMAN'. METHOD FOR DRAWING RODSAND TUBES 0F V'ARYING DIAMETERS.

APPLICATION F ILED NOV, 14. 19W- Patented Apr. 22, 1919.

4 $HEETSSHEET 4.

INVENTOR ATTORNEY LOUIS H. BRINKJHAN, 0F GLEN RIDGE, NEW JERSEY.

METHOD m :onnwme nons AND TUBES or vnarmo mmn'rnas.

' Specification of Letters I atent. Patented Apr. 22, 1919.

Original application filed August 8, 1917, Serial No. 185,005. :Divided and this application filed November 14 1917. Serial No. 201,925.

To all whom it may concern:

Be it known that I, LOUIS H. BRINKMAN a citizen of the United States, residin at Glen Ridge, Essex county, State of ew Jersey, have invented newand useful I'mprovements in Methods for Drawing Rodsmultitude of other applications. This application is a division of my application S. N. 185,005, filed August 8th, 1917.

.One object of the invention is to provide methods for drawing a tube of varying diameters without necessitating the use of a mandrel or inside support, the tube however, accurately holding its predetermined form. n

, Where it is attempted to impart a taper to a tube by heating it and drawing it through a pass, without an inside support,

the pass being gradually reduced in dlameter as the tube is drawn longitudinally, it is found that thetube is fiuted' orooved longitudinally and crushed inwar y into irregular shapes. This is because the tube in the region of the pass must be heated sufliciently to .be soft enough to be acted on.

by the pass and, being in this condition and without any interior support, there is nothing, 01' practically nothing, to support the tube in its proper position against the crushing of the inwardly movin parts of the pass. I have found that t e above mentioned' adverse conditions may be remedied and an improved method of reducing the diameter of the tube provided by cooling the hot metal after it has been acted on by the passto reduce it to the desired dimensions,

this cooling being to such a degree that it. maintains this desired condition of the tube and in such proximity .to the hot metal being acted on by the pass, that this hot metal will be supported against distortion under the action of the inwardly moving pass members. The operation-according to the present invention is very difl'erent from that of reducing the diameter of a tube by rolling it down. According to the-rollmg process the invention is illustrated,

. the. metal ofthe tube is crushed inwardly.

metal is pushed along the tube ahead of the pass. The result is that as the tube is decreased in diameter the wallof the tube is also decreased in thickness. Starting therefore with a tube of uniform diameter and thickness of wall and of a given length, the resulting tube will be not only of a diameter tapering from the large to the small end but will also have its wall thickness tapering, being thickest at the end of large diameter; and further the resulting tube will be of greater length than the original by reason of the movement of the metal lon 'tudinally ahead of the pass above referre to. This secures a most economical distribution of the metal for many purposes. Thus masts, flag'poles'and many other structures require greatest strength at their butt ends, that is the ends of greatest diameter, while at the tip but little strength is required, the strength requirement tapering ofl between these two extremes. By appllcants invention therefore, it is possible to utilize the excess metal to lengthen the tube instead of retaining the metal at intermediate sections .where it would only cause the strength to be excessive and the weight of the tube unduly large.

Another object of the invention isto cobrdinate the longitudinal movement of the In the accompanying drawings whereby Figure 1 is a side elevation of apparatus whereby the invention may be practised.

Fig. 2 is a section, on an enlarged scale, on the line 22 of Fig. 1.

Fig. 3 isa view mostly in side elevation, but partly in section, on an enlarged scale, of a portion of the apparatus at the left end of Fig. 1, showing the arrangement of driving gearing and motor controller.

Fig. 4 is an end elevation of the apparatus of Fig. 3, with the controller insection.

Fig. 5 is a horizontal section, on an enlarged scale, being on a horizontal plane through the pass and on the line 5-5 of Fig. 9, through the centering rest I.

Fig. 6 is a view showing the reducing pass mostly in vertical elevation and partly in section, and with some of the parts removed for the sake of clearness, viewed from the line 66 of Fig. 5.

Fig. 7 is an axial section of the chuck for securing the end of the tube to the draw head.

- Fig. 8 is a diagram of the electrical connections of the driving motor for the draw chain, and

Fig. 9 is a section on a reduced scale on the 1 1 line 99 of Fig. 5.

v Referring to the drawings, the apparatus comprises a drawbench A on which are slidably mounted a draw head B having a rotatable member to which the end of the tube H or rod to be drawn, is secured; also s1iding on the draw bench is a steady-rest C for the tube, a pass D for reducing the rod or tube and a furnace E for heating the tube. The draw head B, the steady-rest C and the reducing pass D, are driven by a sprocket chain F by means of suitable motor and gear mechanism G. A centering rest I which receives the tube after it has emerged from the pass insures that theaxes of the tube and pass shall coincide. Referring more in detail to the drawings, the draw bench A comprises I-beams 1 and 2 supported upon pillars or legs 3, 4, and 5. Secured to the I-beams is a board or plate 6, whichserves as a support for the upper side ofthe endlesschain F, while a similar board 7 supports the lower part of the chain between the point 8 and its right hand end (see Fig. 1), the slack of the chain being allowed to fall down between the point 8 and the left hand end of the chain. The left hand end of the chain engages the sprocket 9, while the right hand end engages the sprocket 10.

The sprocket 9'is fixed upon a shaft 10,

mounted in bearings in a split gear casing 11, which incloses the worm wheel 12,'which 1s also fixed upon the shaft 10. The gear wheel engages with the worm 13, which'is direct connected to a motor 14 regulated by a suitable controller 15, which is controlled by the ull upon the chain F. This is aceomplis ed in'thestructure shown by mountin elongated boxes as 17, formed in the gear casing. Springs as 18 interposed between the bearing blocks and the ends of the boxes, act against the ull of the chain on the sprocket wheel. The shaft 10 extends into an elongated slot 19 in the arm 20, pivoted to the gear casing at 21. The other end of the arm 20 has a gear segment or rack 22, which engages with a spur gear 23 on the shaft 24 of the controller cylinder 25, the controller cylinder being covered by a casing 26. As the bearing blocks for the shaft 10 move back and forth as indicated, the shaft will have a horizontal motion of translation, and clearances 27 and 28 are provided between he worm wheel and the casing so that the wheel may roll on the worm without afl'ecting the engagement therewith as its shaft moves back and forth. The draw head B comprises two bearing supports 29 and 30 clamped to the chain and sliding upon the I-beams 1 and 2. These supports carry the drawn is entered and said tube is fixed by,

one or more set screws 34 passing through the head and engaging with the tube. To support the tube internally against the action of the set screws, 2. ring or boss 32 surrounding the central opening 33 may be provided at the bottom of the socket and, entering within the end of the tube, the latter is clamped beween it and the set screws. The spindle may be rotated by means of a spur gear 35 fixed thereon, which meshes with a spur gear 36 fixed on the shaft of an electric motor 37, which is mounted upon a bracket extending from the support 29. This motor may be of any suitable type and control.

The steady-rest C comprises a support of which the lower plate 38 slides on the tops of the I-beams 1 and 2; guiding and securing pieces 39 and 40 having lips overhanging the flanges of the I-beams are secured to the plate 38. Also secured to the support are bearings 41 and 42 for a shaft 43 which i has fixed to it drums 44 and 45 on either side of the sprocket wheel 46 which is also fixed to the shaft 43. Upon the drums 44. and 45 shaft 43 are fixed skew gears 50 and 51,

which respectively mesh with the skew gears 52 and 53 fixed upon the shafts of screws 54 and 55, having their-axes radiall of the tube and being rotatably mounted but held against endwise movement in the support 56 of which the plate 38 is a part. Sliding in suitable guides in the support 56, are blocks at 62, so that it can be thrown to one side to permit. the placing of the work in position. The portion 61 may then be thrown back into holding position. and secured by a screw or bolt 63. The part 61 carries a radially sliding block 64 similar to the blocks 57 and 58, which carries a rdtatably mounted roller 65 and has a guiding projection 66 passing through an orifice in the lug 67 on the arm 68 extending from theportion' 61. A spring 69 forces the block 64 inwardly so that the roller 65 is held against the tube H.

The sprocket wheel 46 engages with the chain F and furnishes the driving means for winding up the cables 47 and 48 and also for turning the screws 54 and 55 for moving the rollers 59 and 70 to maintain them in contact with the work H. The gearing ratio and the size of the winding drums 44 and 45 is made such as toproduce the desiredlongitudinal movement of the steady-rest and also the radial feed of the rollers 59 and 3 60 so as to maintain those'rollers in contact with the tube notwithstanding variationsin the diameter of the tube between the rollers. The pass D for reducing the diameter of the work, comprises a support 70' which is fixed upon the stationary frame of the draw bench. Fixed in the support 70 is a chuck frame 71 within which the beveled gear 72 has a'bearing. The hub 73 of this gear has a central opening as shown,- so that the work H may pass through its interior. Rotatably mounted in the frame 71,.are screws as 74 and '75, which are in screw threaded engagement with blocks as 76 and77, which slide in slots as 78 in the face plate 79 of the chuck structure, .the edges as 80 and 81 of the blocks over hanging the edges as'82 and 83 of the slots so that the face plate 79 takes up the thrust of the blocks axially of the chuck. Each of the screw shafts as 74 and 75, carries a beveled gear as 84 and 85,

which mesh with the gear 72, so that the turning of one of .the screws involves the similar turning of all of the other sc rews,so that all of the blocks as 76 and 77 have a simultaneous and equal radial movement. To effect this adjustment of the blocks, the shaft of. one of the screws as 75 is extended and has a spur gear 86'secured against turmng thereon by reascn of the end of the shaft being of square cross section and entering.

into a square hole in the center of the gear wheel. The gear may be secured against sliding ofl' the end of the shaft by a set screw or in any other suitable way, so that gears of dlfl'erent sizes may be interchanged to produce difi'erent speeds of driving of the radial adjusting screws for the roller carrying blocks of the chuck. The gear 86 meshes with an idler gear 87 which is rotatably mounted on a pin 88 having a squared end secured in the slot 89 in the arm 90; this arm being pivoted about the axis of the screw 75 .at one end and at .the other end havinga slot 91 in' which is pressed a bolt 92 which passes through the 'web 93 of the support and serves to lock the arm in any desired position of adjustment. The gear 87 meshes with a gear 94 which is fixed to the shaft 95 of the sprocket wheel 10, which engages with the chain F. It will appear therefore, that as the sprocket wheel 10 and gear. wheel 94 are turned by the chain, the screws as 74 and 75, will be turned to move the blocks as 76 and 77 inwardly. The four blocks 76 and 77. have rotatably mounted upon them the rollers as 97, 98 and 99 adapted to 'bear against the work, one roller being upon each block. Each of the rollers comprises a hardened continuous steel rim 100,'with an interior groove 101 forming one side'of a raceway or the balls 102, the opposite raceway being formed by, the plates 103 and 104, which are clamped together by means of the screw 105, which is screwed into the block 76. The central portion of the plates 103 and 104 is therefore clamped in a stationary position while a ball bearing is provided for the rim 100, which'is free to rotate. I In order to supply a cooling fluid for cooling the work after it has passed under the rollers, a water supply pi e 106, communicates with passages as 10 and 108 in the radially moving chuck blocks by means of pipes 109, 110, 111, 112, which are connected with pipe 106 by flexible connections 113, 114, 115 and 116. so that the radial movements of the chuck blocks are not interfered with. The pipes 109-112' inclusive,

anay be of iron while the connections 11 116 inclusive may be rubber or other suitable flexible material.

From each .of. the passages as 107, 108, extends one or more channels as 117, which lead to the sides of the blocks just in the rear of the working portions of the reducing rollers, so that the water is projected with force against the hot water for the purpose of chillin it immediately after it has passed under t e reducing rollers so that it willretain its shape. It may be projected against the rolls but generally some of the fluid should 'be projected directly against the work to produce the desired cooling eflect.

Steam is liable to be formed when the water -metal and permitting it to roll off the work with but slight cooling effect. The water should therefore, be projected upon the work with considerable pressure, so that the film of steam tending to be formed upon the work, will be broken through by the force of the jet and the 'water brought into intimate contact with the surface of the work. It has been found in practice that a pressure of 65 pounds per square inch, gives satisfactory results.

The motor may be of any suitable or well known type and the control effected by any suitable or Well known arrangement of connection. In the diagram of Fig. 8, it has been assumed that the motor 14 is a shunt motor, and governed by a resistance in the armature circuit. Thus in the diagram referred to, the armature is indicated at 118 and the shunt field at 119, the shunt field being connected across the constant potential source whilev a reversing switch 120 serves to connect the armature with the source through the rheostat before referred to.

The controlling rheostat'comprises -a resistv ance 121, with taps therefrom connected with the stationary .contacts 122, it being observed that the stationary contact 123 is not con nected with any "of the circuits. The arm 124 connected with the line, moves over contacts 122 and 123 as its shaft 24 is turned by the gear 23 and segment 22. It will be apparent that as the arm 124 moves to the right over the contacts 122, the resistance will be cut into the armature circuit causing slowing down of the motor and when it has been moved to the extreme right, so as to res-t upon the stud 123, the circuit of the motor will be broken and it will accordingly stop; conversely, resistance will be cut out and the speed of the motor increased as the arm moves to the left over the contacts 122 and 123. The motor may be started in the first instance by an ordinary starting rheostat (not shown.)

The rest I is mounted upon the support for the pass and comprises two circular members or plates 125 and 126 having the central bosses or hubs 127 and 128, these members being held together by bolts 129 and having a central hole 130 for the passage of the tube. In the hub 128 are a series of radially sliding plungers 131 extending into the passage 130 at their inner ends and adapted to have their outer ends engaged by a series of cam faces 132 on the inner side of an annular ring 133 surrounding the hubs. A similar set of plungers 134 extending through the hub 127 are engaged by a similar series of cam faces 135 on the ring 133, the series of plungers of the'two hubs respectively being staggered with relation to each other. The spring 136 acts relationship to each other.

upon the arm 137 with a tendency to turn the ring 133 in such direction that the plungers will be forced inwardly by the cams so as to maintain contact with the tube notwithstanding variations in its diameter. The plungers being all forced in equally, they will tend to hold the tube in'the-center of the passage 130 and consequently in line with the axis of the pass, the holding force depending upon the inclination of the cams and the force exerted to turn the ring 133.

The operation of the apparatus may now be traced as follows By operating the motor 14 in a suitable direction, the steady-rest C and the head B are brought into close proximity at the right hand end of the draw bench. The end of the work, that is the tube or rod to be drawn, is secured in the chuck 32 in a manner as before described and passes back through-the steady-rest, the rest I and the pass D into the furnace E. The tube having been sufficiently heated, the drawing operation is started by causing the motor to draw the sprocketchain in such direction as to move the draw head to the left (see Fig. 1). The

rolls as 97, 98 and 99 are adjusted to thediameter of the tube, the desired taper depending upon the amount of radial movement of the reducing rollersfor a given longitudinal movement of the head, this being determined by the gearing between the sprocket chain and the roller adjusting means as before referred to. It will be observed that inasmuch as the radial adjust ing means for the rollers is driven from the same means which drives the draw head, theradial movement of the reducing rollers of the pass will bear a predetermined ratio to the movement of the draw head, so that in tapering a tube, the inter-dependence of the reducing rollers and the travel of the draw head insure that they Will bear the proper As the draw head thus pulls the tube through the pass, the tube is rotated through the instrumentality of the electric mdtor 27, gears 35 and 36 and spindle 31, so'that the operation of the reducing rollers of the pass is extended about the whole circumference of the tube.

As the tube-is drawn. longitudinally and the pass members move inwardly, a wave of is pushed along ahead of the pass as the tube 139 p is drawn through it and the superfluous metal is utilized to lengthenthe tube as has been hereinbefore referred to.

After a section of the tube has been operated upon by the pass, it encounters the cooling. fluid as before referred to and is chilled sothat it retains its shape and isnot distorted by the operation of the reducing rollers uponthe succeeding section of the tube or by any other distorting agencies. This renders unnecessary any mandrel or interior support for the tube during the re ducing operation, so that the difliculties of mounting a mandrel and manipulating a tube of varying diameter upon it are avoided. The metal under the reducing rollers is heated to such a degree that it may be easily reduced by the action of the rollers, but after such action, the material is chilled as has been mentioned.

It is desirable that the steady-rest for supporting the tube should be half way between the draw head and the pass. To accomplish this, the steady-rest moves one-half the distance that the" draw head moves and in a uniformly tapering tube, the rolls of the steady-rest in order to maintain contact with the tube, only move one-half the radial distance that the-reducing rolls move. Accord.

ingly the size of the winding drums 4:4 and is made such that for a given movement of the chain F, the cables47 and 48 will have a length wound up, which is equal to one-half that .movement and consequently the steady-rest wil1 be moved toward the left (see Fig. 1) at a rate of speed one-half of, that of the sprocket chain. Also the gearing between the sprocket wheel 46 and the steady wheels 59 and 60, is such that fora given movement of the sprocket chain 11. e., for a given movement of the draw head, the reducing rollersof the pass-will move radially inwardly a certain .distance, while the wheels of the steady-rest will move inwardly radially one-half of the distance of the reducing rolls, Here again, the driving of the steady-rest, the reducing rolls and the draw head from the sprocket chain, is such that their movements are sure to be properly proportioned and related to each other.

The left hand limit of the draw head having been reached, the end of the tube may be released from the chuck 32, and the tube removed from the apparatus. The draw head and steady-restmay then be returned to their right hand position, a new tube secured in the apparatus, and the operation repeated as before.

It will be seen that increased pull on the sprocket chain due to insufficient heating of the stock drawn through the pass or from other causes, will cause the bearing blocks of the shaft 10' of the drivin be drawn to the right (Fig. 1 against the pressure ofsprings 18, thereby turning the sprocket to arm 2.0v on its pivot which will result in the turning of the controller of the driving motor 14, so asto slow it down. If the pull of the sprocket chainshould be suiiiciently' details recited, Without departing from the scope of the appended claims, and is not, therefore, limited to practice with the structure shown in the drawings, nor to theprecise recited details of method; the appended claims pointing out the invention in accordance with the patent statutes.

What I claim is '1. The method of forming a metal tube which consists in drawing heated metal through a pass adapted to reduce its diam-- eter and chilling the .metal immediately after it has been acted upon by the reducing member of the pass.

2. The method of forming a metal tube of different diameters, which consists in drawing heated metal through a pass, varying the diameter of the pass and chilling the metal immediately after being acted upon in said pass, sufficiently'for it.to retain its shape. I

3. The method of forming a metal tube of difierent diameters, which consists in drawing heated metal, through a pass, varying the diameter of the pass, chilling the metal immediately after being acted upon in said pass 'sufiiciently for it to retain its shape, and meanwhile relatively rotating the and varying the diameter of the pass during such drawing in predetermined relation to the longitudinal movement of the metal through the pass.

5. The method of forming a rod or tube of difierent diameters, which consists in drawing the metal through a pass, supporting the metal by a steady-rest and moving the steady-rest longitudinally of the work at a speed less than that at which the work is drawn through the pass.

6. The method of forming of difierent diameters, which consists in drawing the metal through a pass, supporting ing the metal by a steady-rest and moving the steady-rest longitudinally of the work at one-half the speed of that at which the work is drawn through the pass.

7. The method of forming a rod or tube of difi'erent diameters, which consists in drawing the metal through a pass and supporting the metal by a steady-rest, having a rod or tube i radially movable supporting members, 1130' which are moved in a pre-determined relation to the longitudinal speed of the work.

8. The method of forming a rod or tube of different diameters, which consists in drawing the metal through a pass, supporting the work by asteady-rest having a radially moving supporting member and varying the diameter of the pass and moving the supporting member of the steady-rest in a pre- 10 determined relation to the longitudinal speed of the Work.

9. The method of forming a rod or tube of different diameters; which consists in" drawing the metal through a pass, meanwhile progressively reducing the diameter of the pass, and regulating the pull upon the work in response to the resistance opposed by the work thereto.

In testimony whereof I have signed this specification this 13th day of November, 20

LOUIS BRINKMAN. 

